It's impossible to list all the game features that were added to Tibia from player proposals, as this information can also be given in the feedback form, by email, not recorded, etc. I wanted to share with you some noteworthy links (my sources) to find most of this information and I'll give you all the examples I possibly can. Keep in mind, some of the proposals are old, and some parts might've been implemented and not the complete idea.
Brighid Grand Explorateur - Applying to TibiaQA team as ModeratorNovember 19, 2024
Looking for new TibiaQA staff membersJuly 12, 2024
Interview with Solkrin - lead of the Customer Support team at CipSoftDecember 20, 2023